The San Diego Chargers had a horrific defense in 2011 when they ranked 20th in yards per rushing attempt allowed, 28th in yards per pass attempt and allowed an NFL high 49 percent conversion rate on third downs. San Diego also ranked 23rd in the NFL with 32 sacks which contributed to their struggles.

San Diego improved last season when they ranked fifth in fewest yards per rushing attempt allowed, 11th in sacks and 12th in yards per pass attempt. However, the New York Giants, the Buffalo Bills and the Washington Redskins were the only teams to allow a higher conversion rate on third down than San Diego in 2012.

This is one area in which San Diego has to improve in 2013 because allowing teams to convert at such a high rate gives them more opportunities to put points on the board. Mental lapses and breakdowns in coverage can lead to opponents converting, so there has to be better communication between the defenders to make crucial stops.

San Diego lost one of the team’s best pass rushers over eight of the last nine seasons when Shaun Phillips left in free agency, so it will be up to Dwight Freeney to replace him and help Corey Liuget in pass rush situations.

John Pagano will enter his second season as San Diego’s defensive coordinator, and he will have to come up with different schemes to confuse opponents on third downs.

San Diego will also have a new secondary, which will more than likely include Derek Cox, Shareece Wright and Marcus Gilchrist to go along with the returning Eric Weddle. Cox, Gilchrist, Weddle and Wright will have to come up big for the team to get more stops in passing situations.

There were only eight teams that allowed fewer yards per play in 2012, but San Diego needs to stop teams from converting so often on third downs.